Submatrix sum query best case O(1)

#1

if we take prefix matrix into consideration, prefix matrix will take O(n^2) complexity to build but in the video it is explained that it will take O(1) complexity to solve. The mentor didnt take building prefix matrix into consideration

#2

hello @

yeah building matrix will be n^2. mentor is talking about time to handle each query which will be O(1) after precomputation

#3

so what is the best approach brute force one or prefix matrix one as both will take n^2 if we look at the entire code.

#4

to handle MULTIPLE queries the prefix precomputation approach is better.